Renovation experts all agree that most wall removal mistakes stem from this initial blunder – here's how you can avoid it

If you're planning on undertaking significant renovation work at home for the first time, then it's incredibly helpful to know the errors to dodge so that your project runs smoothly. And while there are a few mistakes to avoid when you knock down walls and remodel your home's internal layout, they all stem from one major blunder — a failure to prepare effectively.

Knowing how to remove an internal wall is essential if you want to rework your home's configuration so that it's better suited to modern life. But while this renovation project can be transformative, it also has potential to go horribly wrong, especially if you are dealing with a load-bearing wall.

To help ensure project success, I asked design and building pros about the one mistake that homeowners should avoid when knocking down or altering walls, and it turns out, they all agree that this gaffe is the one to be avoided at all costs.

What's the worst mistake you can make when knocking down internal walls?

Improper planning is the worst mistake you can make when knocking down internal walls, and it can have far reaching consequences. So it's crucial that you plan carefully, and use the advice and skills of professionals to avoid these common pitfalls:

• You knock down the wrong wall. 'You should always take time to plan the potential new layout (with professional advice) and how it can be designed,' says Paul Kerr, a building and landscaping specialist at Beatsons. You might have your sights set on removing a specific wall, but expert design input might actually highlight another wall as the one to remove, that could open up your layout in a way you hadn't predicted.
• You knock it down when you should have just altered it. Not all walls need to be removed in their entirety. It might be that by opening up part of the wall, or adding a new doorway is all you need to solve any flow or lack of light issues.
• You fail to check if it's load-bearing. Removing a load-bearing wall without the proper process in place could be disastrous and incredibly costly. 'You have to be certain the structure of the building isn't compromised, and should always seek professional advice and support on which walls are load-bearing and which are not,' adds Paul.

• You overlook hidden services. You should always check if there are pipes or electrical wires located inside the wall, even if it isn't load bearing. To help, this Amazon stud finder wall scanner (£24.69) is essential. Once you've located the pipes and wires, make sure they are decommissioned before you start removing the wall.
• You underestimate the disruption it causes. 'Removing a wall can cause significant dust and mess, so preparation is key. Use dust sheets, seal off adjoining rooms and consider temporary ventilation or filtration to protect finishes,' advises interior designer Susie Pfeiffer from Pfeiffer Design.
• You forget about the finishing touches. Before you knock down the wall, you'll need to plan the finishing touches that will make the space look complete. This could be anything from coving and skirting boards to flooring and furniture placement. Ignoring this preparatory step could leave you with a lack lustre finish and a space that doesn't quite feel right.
• You budget inaccurately. Not all walls are the same, and as such, there's no one price-fits-all. Knocking down a non load-bearing partition wall is going to be more cost-effective than removing one that is acting as a structural support. So make sure you understand exactly what your wall removal plans entail so you can allocate funds accordingly. Use our guide to how much it costs to remove an internal wall to help.

To help boost your confidence of taking on a project like this, heed the advice of a serial renovator and the lessons she learned from knocking down walls on a DIY basis.